1. Technical Field
Exemplary embodiments of the present invention relate to an encryption technology and more particularly, to an encryption technology using an encryption table.
2. Description of the Related Art
Generally, a cryptographic algorithm assumes that an attacker cannot see an intermediate process of the operation of the cryptographic algorithm which is running. The assumption for an attack level of such an attacker is called as a “black-box” attack assumption. However, attacks in a code debug level such as memory manipulation, memory dump and the like are also possible in an actual environment. Assumption that an attacker can modify with knowing an attack operation median value is called as “whitebox” attack assumption. The cryptography designed to be remained secure against the whitebox attack assumption is called as “whitebox cryptography”. The “whitebox cryptography” which is currently used is that an encryption key hides a table key to conceal the process of operation to provide identical result to that from the black-box cryptography through operation with a lookup table.
However, even though a key is hidden in an operation table, it is still vulnerable to a codelift attack which dumps the entire memory.